Tomatoes are the most popular vegetable plant grown. And really, no garden would be complete without them - they require relatively little space for large production. Each plant, properly cared for, yields 10 to 15 pounds or more of fruit.

The Gwinnett County Extension office receives more calls about tomatoes than any other vegetable. Using proper cultural practices and planting disease-resistant varieties will help yield healthy, tasty tomatoes in the garden.

Tomatoes are warm-season plants that must be planted after all danger of frost has past. They can be grown from seed or, preferably, from transplants.

How many tomato plants should you plant? That depends on how many tomatoes you want to care for. A few well-cared-for plants can produce better quality fruits in higher numbers than many that have been neglected.

Tomatoes need full sun, and at least 1 inch of water per week. They prefer well-drained soil heavily amended with organic matter, such as compost and manure. The addition of organic matter increases the plant's ability to absorb water and calcium.

Tomato plants should be fertilized every four weeks with a 10-10-10 balanced fertilizer.

Tomatoes can develop roots all along their stems, so plant them deeply to form a strong root system. Prune out any suckers arising from the roots or the nodes, and remove branches and leaves touching the ground.

The plants tend to grow tall and heavy, and will fall over. To prevent toppling tomatoes, stake the plants with wooden stakes, tie the plants to a fence or use tomato cages.

Tomato varieties come in all sorts of shapes, sizes and colors. Determinate tomatoes grow in a more compact bush form and produce most of their fruits at the same time. Indeterminate varieties set fruit clusters along the vine, and bear continually all season long. The small, cherry tomatoes are an example of indeterminate tomatoes.

Some varieties have been bred to have resistance to various diseases that tomatoes are susceptible to. The plants are not immune from the diseases, and good cultural practices are a must. Resistance is listed on the plant label using these abbreviations: V for Verticillium wilt, F for Fusarium wilt, N for nematode, TSW for tomato spotted wilt virus and T for tobacco mosaic virus.

Insecticidal soaps can control many of the insect pests that typically affect tomatoes, such as whiteflies, hornworms and aphids. Pesticides with Bt, or Bacillus thuringiesis, are useful in controlling certain caterpillar pests.

For more questions about growing tomatoes, contact the Extension office.

Timothy Daly is an agricultural and natural resource agent with the Gwinnett County Extension Service. He can be reached at 678-377-4010 or timothy.daly@gwinnettcounty.com.